The present invention relates to a seat belt system and, more particularly, to a mechanism for feeding of a locking clasp and/or a belt strap of a seat belt system having a belt holder into a position wherein the locking clasp and/or belt strap may be easily gripped so as to enable a fastening of the seat belt.
A seat belt mechanism for, preferably, a two-door passenger motor vehicle, has been proposed wherein, after a closing of the vehicle door and a turning on of the power, a servo mechanism associated with the vehicle door, is adapted to bring a feeder arm, together with the locking clasp and/or belt strap, from a rear position, not impairing free access to the back seats, by a straight feeding movement to a front position assigned to the driver or front seat passenger of the motor vehicle. The feeder arm, immediately after a completed buckling operation, or when the buckling operation does not take place during a predetermined time interval, returns to the starting position where an overload safety device is provided which, for example, in situations wherein there is an unusual rise in force, switches off the servo arrangement.
In, for example, Offenlegungsschrift No. 27 13 172, a mechanism of the aforementioned type is proposed wherein, in response to the overload safety device, the feeder arm stays in the respective position, thereby severely impairing the free access or passage to the rear seats of the motor vehicle. Operational experiences with such mechanisms have shown that the overload safety device, in the course of a feeding movement, especially on the passenger front seat side, is triggered much more frequently than assumed because very often, after the front seat passenger gets into the vehicle, the vehicle is accelerated or slowed down again before the front seat passenger has buckled the seat belt, and an automatic locking of the belt roller takes place during such process.
The aim underlying the present invention essentially resides in providing a seat belt system which includes an overload safety means constructed in such a manner that only in situations of a permanent disturbance, is the safety device brought into a condition for preventing a renewed switching on of the servo arrangement and a temporarily occurring blocking of the belt roller of the safety belt system does not prevent the use of the seat belt.
In accordance with advantageous features of the present invention, a safety belt system is provided wherein, when an overload safety means responds during a feeding movement, the servo arrangement is reversed and, upon reaching a rear end position, a new feeding movement automatically takes place. After a front end position is reached by the feeding arm, the servo arrangement is also reversed and the feeder arm is returned by a small amount that releases the blocking effect of the belt roller that may have occurred. After an at least one-time response of the overload safety means during a feeding movement and with a first-time response during a return movement, a new start of the servo arrangement is possible only after the particular disturbance acting on the safety belt has been corrected or eliminated.
In accordance with further advantageous features of the present invention, when the servo arrangement is stopped in response to the overload safety means, the feeder arm may then manually be brought to a rear starting position, thereby enabling unimpaired access to the back seats of the vehicle even if a disturbance has occurred.
Accordingly, it is an object of the present invention to provide a mechanism for feeding of a locking clasp and/or belt strap of a seat belt system having a belt roller which avoids, by a simple means, shortcomings and disadvantages encountered in the prior art.
Another object of the present invention resides in providing a mechanism for a feeding of a locking clasp and/or belt strap of a seat belt system of a motor vehicle which does not impair access into and out of the motor vehicle.
Yet another object of the present invention resides in providing a mechanism for a feeding of a locking clasp and/or belt strap of a seat belt system which is responsive to an overload safety means so as to automatically effect a new feeding of the locking clasp and/or belt strap.
A further object of the present invention resides in providing a mechanism for a feeding of a locking clasp and/or belt strap of a seat belt system which is simple in construction and therefore relatively inexpensive to manufacture.
A still further object of the present invention resides in providing a mechanism for a feeding of a locking clasp and/or belt strap of a seat belt system which functions reliably under all load conditions.